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I've had COVID, am I protected? Do I still have to respect physical distance, wash my hands, wear the mask...?

Text updated on 2021-05-09


One doesn't know how long they're immune after their first SARS-CoV-2 coronavirus infection. A few cases of re-infections have been observed, but it is not yet known how often re-infections occur. It is therefore necessary to remain vigilant and continue to apply barrier gestures and to wear a mask.

Yes, you are protected but the duration of protection is unknown at this time. The duration of protection varies according to the viral infections. For cold coronaviruses, immunity is around 30 months. For the measles virus, which is not a coronavirus, immunity lasts for life.

In the case of the coronavirus SARS-CoV-2, it is still too early to know how long the protection will last. The duration could be a few months. With the hindsight we have, we estimate that the duration of protection is at least 6-8 months. We must therefore remain vigilant and continue to respect the barrier gestures, wash our hands frequently and wear a mask, even if it is restrictive.

After an infection with COVID-19infection, it is possible to find out if you are immune by doing a serological test. See the question What are the tests to find out if I have already had COVID-19 ?

There are a few known cases of coronavirus re-infection, some with more severe symptoms the second time and some without symptoms the second time. See the question Can we catch COVID twice?. If you are re-infected with theSARS-CoV-2 virus, have an asymptomatic form, and no longer follow the barrier gestures or mask wearing, you risk transmitting the coronavirus and unknowingly infecting others.

Furthermore, our hands can be a vector of transmission without us being infected. If we touch a coronavirus-contaminated SARS-CoV-2surface, we can carry it to another surface. So you can infect other people without being infected with the coronavirus yourself.

Finally, hand washing protects against many other viruses and bacteria. Therefore, you should continue to wash your hands to prevent the transmission of COVID-19, just like other infections!


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Sources

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Immunity to the measles virus lasts a lifetime.

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In this preprint, the authors report the case of a 25-year-old patient from Reno, Nevada, who developed a severe form of COVID-19 (with hospitalization and need for continuous oxygen supply) one month after the end of symptoms associated with a first infection that did not require hospitalization. Differences in viral RNA sequences between the two infectious episodes confirm that this is a reinfection and not a resurgence of the first infection.

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Measurement of the stability of the virus under different environmental conditions.

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Several people in the same family have been infected by asymptomatic individuals.

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Study in 176 patients infected with the SARS-CoV-1 virus which shows that the average duration of immunity against this disease is 24 months.

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In this longitudinal study, a cohort of 12,541 health care workers was followed for 31 weeks. The presence of anti-spike antibodies (to the coronavirus Spike protein) was associated with a reduced risk of infection with SARS-CoV-2. In these individuals with anti-spike antibodies, no symptomatic infections and only two cases of asymptomatic forms were observed. This suggests that prior infection with SARS-CoV-2 resulting in antibody production is associated with protection from reinfection for most individuals for at least 6 months.

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In this longitudinal study, 188 individuals with COVID-19 were recruited with predominantly asymptomatic forms (2% asymptomatic). Five to 8 months after their infection with SARS-CoV-2, anti-spike antibodies (against the Spike protein of the coronavirus) and anti-RBD antibodies (against the Receptor Binding Domain, a domain that binds to human cells) were detected in about 95% of the individuals. These results indicate that sustained immunity to secondary infection with COVID-19 infection is possible in most individuals.

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Further reading

How does she get COVID-19 ?

Why put on a mask?

Do I have to wear a mask if I don't have any symptoms?